What is Epigenetics

Epigenetics is the mechanism by which environmental changes alter the behaviour of our genes. This involves a process known as methylation, which occurs when a chemical known as methyl, floating around the inside of our cells, attaches itself to our DNA. When it attaches, it can inhibit or disrupt the activity of a gene and block it from making a particular version of a protein in our bodies. Many life events can critically affect DNA methylation levels in our bodies including: diet, illnesses, ageing, chemicals in the environment, smoking, drugs and medications.

Epigenetic changes produce variation in disease patterns. Recent experiments that have looked at methylation levels in pairs of identical twins, back the theory. Identical twins who have different tolerances to pain have been shown that they have different states of methylation. Similar results have been produced for depression, diabetes and breast cancer. In each case, genes have been found that are switched on in one twin and switched off in the other twin. This often determines whether or not they are likely to get a disease.

Epigenetic changes are not just simple environmental changes, however. They influence a person's genes and can have an effect that can last for two or three generations in extreme cases.